Presses comprising a movable platen driven by toggle levers



May 11, 1965 E. BOLLIGER 3,132,583

PRESSES COMPRISING A MOVABLE PLATEN DRIVEN BY TOGGLE LEVERS Filed Dec. 26, 1962 3 Sheets-Sheet 1 E. BOLLIGER May 11, 1965 PRESSES COMPRISING A MOVABLE PLATEN DRIVEN BY TOGGLE LEVERS Filed Dec. 26, .1962

3 Sheets-Sheet 2 May 11, 1965 E. BOLLIGER' 3,182,583

PRESSES COMPRISING A MOVABLE PLATEN DRIVEN BY TQGGLE LEVERS Filed Dec; 26, 1962 3 Sheets-Sheet 3 United States Patent 3,182,588 PRESSES COMPRISING A MOVABLE PLA'IEN DRIVEN BY TOGGLE LEVERS Edwin Bolliger, Prilly, Switzerland, assignor to J. llobst and Son S.A., Prilly, Switzerland, a corporation of Switzerland Filed Dec. 26, 1962, Ser. No. 247,250 Claims priority, application Switzerland, Oct. 23, 1962, 12,457/62 5 Claims. (Cl. 100--286) The present invention refers to a platen-press having a movable platen which is driven by toggle levers and which has a convex active surface which is brought into contact by a rolling motion against a fixed platen having a fiat surface.

It is an object to provide improvements in the drive of the movable platen of a press of the above type.

The invention will be described by way of example in the embodiments shown in the drawing wherein:

FIG. 1 is an elevation view in section of a press,

FIGS. 2-5 schematically show for the press various positions of the movable platen relative to the fixed platen,

FIG. 6 is a sectional view taken along the line VIVI in FIG. 7, and

FIG. 7 is a sectional view taken along the line VII- VII in FIG. 6.

In FIG. 1, there is shown a press whereln frame 1 1s integral with the fixed upper platen 24, againstwh ch the lower movable platen 23, the active face of which is convex, is applied by a rolling motion.

The application of pressure takes place by means of four toggle levers 21, 22 driven by the rods 17, 18 con trolled by coaxial eccentrics rigid with the central or mainshaft 15, accomplishing one revolution by working cycle.

The driving of shaft is effected through a wormscrew 9 and a worm-screw 10, supported on the driving shaft 11 having a fly-wheel 12, the drive motor not being represented.

The operation of such a press has been obtained only by very complicated means, in particular by profiled cams of slides (not shown) between the platen 23 and the shaft 15 which are difficult to design and produce because of the relatively complicated motion of the lower platen. Thus, the toggle levers perform one after another their tensile motion, corresponding to the application of the movable platen against the fixed platen, the first one has to carry out a swaying motion ensuring rolling without sliding on the second one, whereupon the toggle levers are turned back on themselves, and the movable platen performs a back motion in which it is at a distance from the fixed platen sufficient to allow the evacuation of the processed piece (for instance a cut out or corrugated cardboard sheet) and its substitution by a piece to be processed, for instance by means of transversal gripper bars 13 driven by endless conveying chains 14. The operation of the gripper bars is entirely conventional and briefly it may be stated that the gripper bars operate to transport a fresh piece between the spaced platens While removing the piece which has been operated upon all in synchronization with the movement of the lower platen.

According to the present invention, a solution to the drive of the lower platen is provided making use of simple means, easy to obtain with accuracy.

On the main driving shaft of the toggle levers, performing one revolution per working cycle there is arranged at least one cam imparting a swaying motion to a lever pivoted directly beneath the active face of the movable platen and being continued above of this pivoting point to engage the movable platen to enable the platen to slide and pivot at the same time in relation to thelever, the tying point of the connecting rods joining the main 3,182,588 Patented May 11, 1%65 shaft to the jointing centers of the toggle levers being distant from each other by an are less than 180.

FIGS. 2 to 5 correspond to the initial, middle end and lowered position of the movable platen with respect to the fixed platen, that is to the complete working cycle.

In FIGS. 2 to 5, the main shaft 15 accomplishes one revolution per cycle and a pair of cams 16 are supported on the shaft 15 one at either end. In this respect, it will be appreciated from a consideration of FIGS. 6 and 7 that the general arrangement of the support at only one end of the platen 23 has been shown, the opposite end having an identical mirror image arrangement.

Opposite connecting rods 17, 18 are linked to the shaft 15 by joints 19 and 20 respectively and operate the median joints of the respective toggle levers 21 and 22, which are connected to the movable platen 23. The platen 23 has a convex surface for cooperating with the plane lower face of the fixed platen 24.

The joints 19 and 20, which define a central :angle in the shaft 15 of about 90 turn with the shaft 15 in the direction of the arrow 25, to impart a swaying motion to the platen 23 by first applying the right-hand end against the platen 24, then the center (FIG. 3) and finally, the left-hand end (FIG. 4), thereafter it will perform an inverse back swaying in moving simultaneously away from the upper fixed platen.

By dimensioning judiciously the proportions between the elements of the toggle levers, their driving rods and the central angle defined between the joints 19, 20 on the shaft 15 the desired contact of the lower platen with the upper platen can-be obtained. But it will not be :a pure rolling without sliding. To effect such a motion, it is necessary to use a forced guiding of the platen 23, in which the cam 16 participates.

Against cam 16 there is applied the lower end of a lever 26 pivotally secured to a fixed axle 27 situated under the active face of the platen 23.

Above fixed axle 27, the lever extends and its upper free end leads to a block 28 forming a guiding shoe in a slide 29 extending symmetrically with respect to the con vex face.

Thus, the block or shoe 28 can slide in the platen 23 in a direction substantially normally to the surface of the platen 23 while undergoing pivotal movement with respect to the upper end of lever 26.

In the initial position of FIG. 2, the shoe 28 is as far as possible to the right (in the drawing), since the lever 26 is at the smallest eccentricity of the cam beingpractically 1011 the bisectrix of the angle inscribed between the joints 19 and 21) of the connecting rods 17 and 18.

After about a quarter of a revolution of the shaft 15 (median position in FIG. 3), the center of the movable platen is applied against the fixed platen, and the extensions of the two toggle levers are identically oriented. Furthermore, the shoe 28 is in the vertical axis of symmetry x-y-and, all the elements of the assembly, with the exception of the lever 26, are symmetrically arranged with respect to this axis.

After about another quarter turn or a total half turn from the original position of the assembly, the position of 1 FIG 4 is obtained, which is opposite to that of FIG. 2,

corresponding to the application of the left-hand end *of the platen 23 against the platen 24, the shoe 28 being shifted to the left a distance as much as it is to the right in FIG. 1.

By means of appropriate relationships between the dimensions of the cam, those of the lever 26 and the position of the articulation of the shoe 28, the movable platen is constrained to perform a perfect rolling motion without sliding against the platen 24 in the manner as shown.

During the second half turn of the shaft 15, the joints 19 and 20 will pass at a lower symmetrical position as shown in FIG. 5. The joint 19 is then to the right and the joint 20 to the left. The centers of the two toggle levers will occupy their nearest positions to each other (the farthest are realized in FIG. 3) and the two ends of the platen 23 will be simultaneously lowered so as to provide a gap between the two platens, said gap permitting the transport between the platens of the pieces already processed and those to be processed.

In the next quarter turn the assembly assumes the position in FIG. 2 for a subsequent operation. FIGS. 6 and 7, show in detail an embodiment of the movable platen guiding means which has been described with respect to schematic representation.

In the platen 23, a rectilinear groove 31 is provided, constituting slide 29 and in which is slidably supported shoe 28.

33 represents a tool which is applied to the face of platen 23.

This latter platen 23 is driven in the manner already described in FIGS. 2-5 by toggle levers. The shaft 15 supports the cam 16 and operates the lever 26 pivotally connected at 37 to the shoe 28.

The lever 26 is rotatably supported on axle 27 which is secured to element 39 of the frame. Screws (not shown) extending along axes 40 secure axle 27 to element 39 at the head 41 of the axle 27.

A similar head 42 and screws (not shown) and extending along axes 42, 43 secure pivot 37 in position at the end of the lever 26. Finally, a spring 44 urges the roller 45 of the driven end of the lever 26 against the cam 16.

Thus, while the shaft 15 undergoes a rotation of one turn, the cam imparts to the pivot 37 a lateral swaying motion around the fixed shaft 27, allowing at the same time the lifting, the lowering and the modification of the inclination of the platen 23 with the shoe 28 and in relation to this latter shoe. These are the conditions represented in FIGS. 2 to 5.

Of course, there will be a similar mechanism at both ends of the shaft 15, i.e. on either side of the platen.

What I claim is:

1. A platen press comprising a fixed platen, a movable platen having a convex surface and opposite ends, toggle levers connected to said movable platen, a drive shaft adapted for rotation, a pair of connecting rods connected to the drive shaft and to the toggle levers to cause the toggle levers to alternately lift one end of the movable platen and then the other end of the movable platen as the drive shaft undergoes rotation, a cam supported on said drive shaft, a lever having opposite ends and secured for pivotal movement intermediate said ends about a fixed axis, one of said ends of said lever being in contact with said cam to follow the motion thereof as the drive shaft undergoes rotation, and means connecting the opposite end of the lever to the movable platten for pivotal movement and for sliding motion in a direction normal to the surface of the movable platen to constrain the movable platen to undergo a swaying movement concurrent with the raising and lowering of the ends thereof to cause the surface of the movable platen to roll without sliding on the fixed platen and then be withdrawn from the fixed platen for each rotation of the drive shaft.

2. A platen press as claimed in claim 1 wherein said connecting rods are connected to the shaft at locations which are less than 180 apart.

3. A platen press as claimed in claim 1 wherein said means connecting the opposite end of the lever to the movable platen includes a shoe, a slideway extending along a line which divides the convex surface symmetrically, said shoe being supported in said slideway for sliding movement and means pivotally connecting said opposite end of the lever with the shoe.

4. A platen press as claimed in claim 1 wherein said cam is eccentrically supported on said shaft.

5. A platen press as claimed in claim 4 wherein said cam is eccentrically offset from the center of the drive shaft in a direction away from the connections of the connecting rods with the shaft.

References Cited by the Examiner UNITED STATES PATENTS 523,802 7/94 Williams -286 2,130,818 9/38 Soderberg 83-646 3,044,393 7/62 Kury 100286 3,057,241 10/62 Chambon 83-510 FOREIGN PATENTS 611,750 11/48 Great Britain.

845,004 7/52 Germany.

OTHER REFERENCES K 16,179 IG/58 0C, 11/55, Germany (Printed Application).

ALTER A. SCHEEL, Primary Examiner. 

1. A PLATEN PRESS COMPRISING A FIXED PLATEN, A MOVABLE PLATEN HAVING A CONVEX SURFACE AND OPPOSITE ENDS, TOGGLE LEVERS CONNECTED TO SAID MOVABLE PLATEN, A DRIVE SHAFT ADAPTED FOR ROTATION, A PAIR OF CONNECTING RODS CONNECTED TO THE DRIVE SHAFT AND TO THE TOGGLE LEVERS TO CAUSE THE TOGGLE LEVER TO ALTERNATELY LIFT ONE END OF THE MOVABLE PLATEN AND THEN THE OTHER END OF THE MOVABLE PLATEN AS THE DRIVE SHAFT UNDERGOES ROTATION, A CAM SUPPORTED ON SAID DRIVE SHAFT, A LEVER HAVING OPPOSITE ENDS AND SECURED FOR PIVOTAL MOVEMENT INTERMEDIATE SAID ENDS ABOUT A FIXED AXIS, ONE OF SAID ENDS OF SAID LEVER BEING IN CONTACT WITH SAID CAM TO FOLLOW THE MOTION THEREOF AS THE DRIVE SHAFT UNDERGOES ROTATION, AND MEANS CONNECTING THE OPPOSITE END OF THE LEVER TO THE MOVABLE PLATEN FOR PIVOTAL MOVEMENT AND FOR SLIDING MOTION IN A DIRECTION NORMAL TO THE SURFACE OF THE MOVABLE PLATEN TO CONSTRAIN THE MOVABLE PLATEN TO UNDERGO A SWAYING MOVEMENT CONCURRENT WITH RAISING AND LOWERING OF THE ENDS THEREOF TO CAUSE THE SURFACE OF THE MOVABLE PLATEN TO ROLL WITHOUT SLIDING ON THE FIXED PLATEN AND THEN BE WITHDRAWN FROM THE FIXED PLATEN FOR EACH ROTATION OF THE DRIVE SHAFT. 